Tourniquets are used by orthopedists, anesthesiologists and other medical practitioners to stop the flow of blood through an artery by compression, and are typically placed proximally on an upper or lower extremity such as the upper arm or thigh, and occasionally in a more distal position such as on the calf. Inflatable tourniquet cuffs are commonly used in the medical field, and include bladders that are inflated by compressed air, producing enough compression to occlude the arterial flow. For an orthopedist or other surgeon who does extremity surgery, this achieves an avascular, or “non-bleeding,” dry surgical field. By stopping the flow of blood into the extremity, surgery can be performed in that extremity distal to the tourniquet without bleeding. With the artery occluded, no blood flows into the surgical field and the surgeon can perform surgery in what is temporarily an avascular area.
To completely stop the flow of blood, a tourniquet should be applied as high as possible into the axilla or “armpit” in an upper extremity, or into the groin adjacent to the inguinal ligament located at the crease between the lower abdomen and the anterior, or front part of the top of the thigh. Such placement occludes the artery before it begins to divide into its branches, and provides a surgeon with a large operative field for elbow and knee surgery. A large area is needed in order to prep the skin adequately and to drape the area properly so that during surgery, if an incision needs to be extended, the surgeon does not need to cut through drapes to do so.
Tourniquets in the form of blood pressure cuffs, are also used by anesthesiologists to monitor blood pressure during surgical procedures, by nurses in intensive care units, by medical personnel in transitional care units, among others. A blood pressure cuff is often applied and left on for an extended time period, i.e., several days. The cuff is applied as high as possible on the upper extremity in order to more effectively occlude the artery before it branches and obtain a more accurate blood pressure measurement.
In use during a surgical procedure, a tourniquet is applied with continuous pressure for an extended period of time. In the use of a blood pressure cuff during a surgical procedure or in an intensive care or cardiac care unit, the cuff is automatically and repeatedly inflated and deflated at about one to two minute intervals to monitor blood pressure, and can be left on for several days. This adds up to numerous compressions of the skin during a procedure or treatment period.
Tourniquets are commercially available and typically 2 to 6 inches wide for single bladder tourniquets and about 8 to 9 inches wide for double bladder tourniquets (“Bier blocks”). A blood pressure cuff about 4 inches wide is used most frequently by anesthesiologists. For an average size patient, a 4-inch wide tourniquet is used for upper extremity surgery, while a 4- to 6-inch wide tourniquet is typically applied to the thigh for surgeries on the lower extremities.
Tourniquets are generally supplied without padding, and some surgeons and anesthesiologists use a tourniquet without padding underneath. However, this can result in injury to the skin caused by prolonged or intermittent pinching while the surgery is performed or when the blood pressure tourniquet is inflated/deflated to monitor blood pressure.
To avoid skin irritation and damage to the outer layers of the skin by the repeated compression, a soft padding material is typically wrapped around the extremity and the tourniquet is applied over the wrapped material. Typically, 3 to 4 layers of sheet wadding or cast padding such as WEBRIL™ cotton padding (Kendall Company) are used under the tourniquet.
Although desirable, the use of padding under a tourniquet is problematic. The diameter or circumference of the upper arm and thigh decreases from the proximal end (i.e., shoulder, hip) to the distal end (i.e., elbow, knee). In most people, the upper arm and thigh are conically shaped like an ice cream cone, being wider at the top and narrowing toward the elbow or knee. This presents problems in maintaining a tourniquet in a stationary position on the upper part of the arm or the upper part of the thigh. Although the cushioning effect of the padding is a plus, the padding tends to slip distally down the extremity during a procedure. This situation becomes more problematic as the weight of the person increases and the distal part of the extremity is proportionately smaller than the proximal part. In addition, a heavier patient tends to have looser skin and subcutaneous tissues, requiring a higher amount of compression to occlude the artery for surgery or to obtain blood pressure.
Slippage of a blood pressure cuff along a limb causes particular problems for anesthesiologists and surgeons. For surgical procedures, the tourniquet cuff is applied to the upper arm and inflated, blood pressure is recorded, and the cuff is then deflated. As this is repeated over an extended time during the procedure, the cuff slips distally and a different part of the extremity becomes compressed. This change in the location where the blood pressure measurements are taken can result in inaccurate readings.
There have also been numerous complaints about tourniquet slippage down the arm or thigh and causing problems with proper occlusion of the artery during surgical procedures. For a surgical operation performed on an elbow, knee, forearm, hand, calf or foot, as the tourniquet slips distally, compression decreases and compromises the surgical field with bleeding. In addition, the distal edge of the tourniquet is not sterile, and as the edge enters the surgical field, the potential for post-operative infection increases. There have also been problems with the tourniquet or cuff slipping off the underlying padding material onto the skin, resulting in blisters where the skin had been pinched.
Another problem arises when the tourniquet is applied over several layers of cast padding, and the limb is prepped with a wet surgical scrub. An extremity is typically elevated while it is being prepped by a scrub nurse, and fluid that runs up the arm or leg wets the tourniquet and/or tourniquet padding. Most surgical preps include skin irritants and are applied and then wiped or rinsed off the skin. Consequently, compression by a wet padding and prolonged contact with a pre-operative skin prep can result in serious damage to the outer layers of the skin.
In addition, tourniquets that become soiled with blood or other fluids are difficult to clean thoroughly and, in cases of AIDS and other infectious diseases, the contaminated tourniquet is usually discarded. With the cost of tourniquets at about $200 and higher, this can significantly increase the cost of a surgery or other medical procedure.
Therefore, it would be desirable to provide a padding that can be used in connection with a blood pressure cuff and other tourniquets that overcome the foregoing problems.